Influence Of Temperature Research Articles

Electrical Bioimpedance in Milk Adulterated with Water: Measurement Methodology for Quantification, Influence of Temperature, and Mathematical Modelling

Milk has a high nutritional value and is also one of the most versatile products in the food industry. Unfortunately, fraud involving the product is constant and needs to be combated. This work presents a measurement methodology to perform the electrical impedance analysis in food. The influence of temperature on the measurements has been evaluated through mathematical models specially developed for identifying the fraudulent activity of adding water to milk. The bioimpedance measurements have been performed in a sample container with a four-electrode measurement system and a digital oscilloscope. Samples of 150 mL were analysed, prepared using whole UHT milk adulterated with distilled water in different % by volume (V/V), at temperatures of 16, 28, and 37 °C. The proposed measurement methodology has been validated and showed sensitivity for analysis in milk, revealing the influence of temperature on the impedance values; from the results mathematical models were proposed for investigating adulteration in milk. This work deals with the design of a device capable of measuring bioimpedance in milk with a view to its application in physicochemical analyses. The influence of temperature on the impedance values was also evaluated to propose mathematical models to facilitate analysis with complex factors and matrices.

Pressure and distance measurements under temperature interference by using impedance change of spiral conductive polymer composite

To realize the compressive-pressure and non-contacting-distance measurements in the curved-interlayer-structure of modern-industrial-equipment under temperature-interference, the influences of temperature on the impedance-variations of the spiral conductive polymer composite (which possesses the tunneling-effect-based-conduction, the intrinsically-flexibility and the ability to induce eddy-current-effect) caused by the pressure and distance are studied. The pressure/distance-impedance-property repeatability increases with the increment of experimental-times, and the pressure/distance-impedance-characteristic is monotonically decreasing/increasing. When the temperature increases from 10 °C to 40 °C, the normalized-impedance-amplitude attenuates/increases and the normalized-impedance-angle raises/decreases under the same pressure/distance, and the sensitivities for the pressure/distance-impedance-property increases. The measurement system based on the two-levels-interpolation is developed and tested under temperature-interference. The testing-results show that the pressure-measurement-error is 8 % F.S. (0–0.65 MPa) and the distance-measurement-error is 5 % F.S. (0–2 mm). The results lay the foundation on revealing the distance/pressure/temperature-sensing-mechanisms of spiral composite, and verify the feasibility of using the spiral composite to measure the pressure/distance under different temperatures.

Sustainable Jam with Apple Pomace: Gelling, Rheology, and Composition Analysis.

Fruit juice processing can generate significant waste, but efficiently repurposing some of its byproducts not only reduces environmental impact but also adds value, thereby enhancing sustainability in the food industry. This work assesses the use of hydrocolloids in jam preparation and the influence of time and temperature on gelation in the presence of apple pomace. The effects of different processing conditions were analyzed using response surface methodology. Viscosity, elastic modulus (G'), viscous modulus (G″), and firmness were measured. Results indicated that both time and temperature significantly improved rheological and textural properties. The optimal conditions (35.6 min and 84.2 °C) yielded a viscosity of 3.66 × 10⁴ ± 4.49 × 102 Pa·s and a G' at 1 Hz of 2596 ± 128 Pa. The final product exhibited the desirable texture, was free of added sugars, had low lipid content, and retained its bioactive compounds. Applying apple pomace in the formulation allows a more efficient hydrocolloid system, promotes a circular economy, and combats food waste.

Effect of Stand Age on Soil CO2 Emissions in Pedunculate Oak (Quercus robur L.) Forests

The emission of CO2 from soil represents one of the most significant fluxes between terrestrial ecosystems and the atmosphere. It is crucial to investigate the impact of stand age on soil CO2 emissions in order to evaluate the possibility of carbon sequestration through the establishment of new forests. In this study, soil CO2 emissions and microclimate variables (soil temperature and moisture) were investigated in the chronosequence of three differently aged stands (4-, 14-, and 70-year-old stands) in floodplain pedunculate oak (Quercus robur L.) forests in Serbia. This study highlights how the artificial regeneration of pedunculate oak forests (establishment of new stands) can affect CO2 emissions from soils. Seasonal fluctuations in soil CO2 emissions were observed in all of the monitored stands, along with variations in the influence of soil temperature and moisture. Multiple linear regression, incorporating soil temperature, soil moisture, and their interaction, offered the most comprehensive explanation for the variation observed in soil CO2 emissions. The seasons had statistically significant effects (p < 0.001) on CO2 emission from the soil in the examined stands during 2022. The youngest stand (4-year-old) had significantly higher soil CO2 emissions (p < 0.05) compared to the older stands over the entire study period (2021–2022). These results showed that the 70-year-old stand (natural high stand) had significantly lower soil CO2 emissions compared to the 4-year-old stand (artificially regenerated stand).

Free vibration of spinning stepped functionally graded circular cylindrical shells in a thermal environment

This paper investigates the free vibration of spinning stepped functionally graded material (FGM) circular cylindrical shells with general boundary conditions in a thermal environment. The artificial spring is implemented to simulate the general boundary constraints. Temperature-dependent material properties change constantly along the thickness direction. The Donnell-Mushtari shell theory is applied to derive the energy functions of thin stepped circular cylindrical shells, where the effect of centrifugal force and Coriolis force is taken into account. The modified Fourier-Ritz method is utilized to derive the frequency equations of the spinning stepped FGM circular cylindrical shells. The influences of spring stiffness, power-law index, and temperature on the traveling wave frequencies are investigated. The influence of configuration on the forward wave frequency and critical speed of three stepped shells, including the one-end thickened, the two-end thickened, and the middle-thickened stepped shells, is discussed. For each configuration, design strategies for the stepped shells are proposed.

An influence of geothermal water, temperature and pressure on the hydration of multicomponent cement binders

Cement pastes of different compositions were hydrated in a geothermal solution with the simultaneous action of high temperature (150 °C) and pressure (18 MPa) for 7 days. The influence of solution on phase composition and compressive strength of pastes was investigated based on the comparison with hydration in water and using TGA, XRD, FTIR, 29Si, and 27Al NMR. The geothermal solution accelerated hydration and pozzolanic reactions. A higher amount of more thermally stable products was formed. Undesired transformation to crystalline α-C2SH in the samples with the highest C/S ratio was restricted. The uptake of carbonates from the solution led to an increased amount of calcite. As a result, increased compressive strength values were determined. Preferential incorporation of Al3+ into the structure of C-(A-)S-H or hydrogrossular phases depended on the composition of cement pastes.

The Designs and Testing of Biodegradable Energy-Absorbing Inserts for Enhanced Crashworthiness in Sports Helmets.

This article addresses manufacturing structures made via injection molding from biodegradable materials. The mentioned structures can be successfully used as energy-absorbing liners of all kinds of sports helmets, replacing the previously used expanded polystyrene. This paper is focused on injection technological tests and tensile tests (in quasi-static and dynamic conditions) of several composites based on a PLA matrix with the addition of other biodegradable softening agents, such as PBAT and TPS (the blends were prepared via melt blending using a screw extruder with mass compositions of 50:50, 30:70, and 15:85). Tensile tests showed a positive strain rate sensitivity of the mixtures and a dependence of the increase in the ratio of the dynamic to static yield stress on the increase in the share of the plastic component in the mixture. Technological tests showed that increasing the amount of the plasticizing additive by 35% (from 50% to 85%) results in a decrease in the minimal thickness of the thin-walled element that can be successfully injection molded by about 32% in the case of PLA/PBAT blends (from 0.22 mm to 0.15 mm) and by about 26% in the case of PLA/TPS blends (from 0.23 mm to 0.17 mm). Next, the thin-walled elements (dimensions of 55 × 55 × 20 mm) were manufactured and evaluated using a spring-loaded drop hammer. The 60 J impact energy was tested in accordance with the EN 1078 standard. The dynamic crushing test included checking the influence of the materials' temperature (-20, 0, 20, and 40 °C) and the impact velocity. It was proven that the maximum deflection increases with increasing material temperature and an increase in the share of the plastic component in the mixture. The PLA15PBAT85 blend was selected as the most effective material in terms of its use as an energy-absorbing liner for sport helmets. Johnson-Cook and Cowper-Symonds material plasticizing models were constructed. Their use during dynamic FE simulation provided results that were in good agreement with those of the conducted experiment.

The Effect of Ultracapacitor on the Performance of Series Range-Extended Hybrid Commercial Vehicle

<div>Toward the goal of “dual carbon economy” development, new energy hybrid commercial vehicles have become the main vehicles to meet the future fuel consumption and emission targets. In order to meet the high requirements of commercial vehicles on power and to minimize the influence of ambient temperature on the power of the vehicle, this study proposes a composite energy storage system (CESS) incorporating ultracapacitors. To further understand the impact of ultracapacitor on the dynamic performance of the vehicle, this study compares the dynamics of series range-extended hybrid pickup trucks with and without ultracapacitor at ambient and low temperatures, as well as the effect of ultracapacitor on the service life of lithium-ion batteries, by means of simulation. The results show that at room temperature (25°C), the addition of ultracapacitor shortens the 0–100 km/h acceleration time of the whole vehicle by 24.4% and improves the off-road climbing performance by 11.7%; at low temperature (−20°C), the addition of ultracapacitor shortens the 0–100 km/h acceleration time of the whole vehicle by 88.8% and improves the off-road climbing performance by 67.9%. Under WLTC, 3% gradient conditions, the ultracapacitor increases the cycle life of the lithium-ion battery by about 9% and reduces heat generation by 11.7%.</div>

Extreme temperature influence on low velocity impact damage and residual flexural properties of CFRP

AbstractIn this work, the behavior of carbon fiber reinforced polymer composites (CFRPs) interleaved with electrospun veils under low velocity impact (LVI) conditions and extreme environmental temperatures was investigated. 2/2 twill carbon fiber/epoxy laminates were subjected to LVI at three energy levels (10, 20, and 30 J), and three temperatures (−50°C, room temperature, and 100°C). Two interleaved configurations were explored (six veils placed symmetrically with respect to the middle plane of the laminate and with respect to the external layers of the laminate). Particularly at room temperature and up to 20 J, nanofibrous interlayers effectively reduced localized deformation (by about 13.0%) and delamination (by about 12.2%) when positioned in the outer ply interleaved configuration compared to the reference laminate. At 100°C, this effect is maintained at 10 J, preventing an increase in the delaminated area. At −50°C and 10 J, the promotion of delamination prevented back surface fiber failure. Regarding post‐impact flexural properties, the presence of nanoveils ensured superior mechanical properties compared to the corresponding reference laminate impacted at the same conditions, demonstrating their efficacy in enhancing the damage tolerance of the overall laminate.Highlights Electrospun veils were interleaved in 20 layers of 2/2 twill carbon/epoxy laminate. Three configurations were tested under LVI at 10 J, 20 J, 30 J, and −50°C, RT, and 100°C. Observed damage modes include delamination, indentation, and back surface fiber cracks. Veils symmetrically placed in external layers limit delamination at 20 J (RT) and 10 J (100°C). Electrospun veils enhanced CFRP bending and residual post‐impact properties at RT and 100°C.

SEARCH FOR METHODS TO INCREASE THE SEDIMENTATION RATE OF THE UPPER FLOATING LAYER OF OIL SLUDGE PITS

Traditionally, oil sludge with a liquid-viscous consistency is separated into petroleum product, water and solid mechanical impurities. A large number of technological devices, including separators, centrifuges, hydrocyclones of various designs, have been developed to carry out the operation of interfacial separation of liquid-viscous oil sludge.On the territory of every oil refinery that has been in operation for decades, there are oil sludge ponds — natural settling ponds in which large quantities of oil waste accumulate.The problem of processing barn oil sludge in the oil production and refining industry has not yet been completely solved. This is due to the high stability of barn emulsions, the peculiarities of their composition and properties, which are constantly changing under the influence of temperature and various processes occurring in them.The article presents the results of research aimed at identifying the possibility of destruction of a persistent oil-water emulsion taken from the upper floating layer of an oil sludge pit and its preparation without changing the technological scheme and technological parameters.The results of laboratory studies on the destruction of oily liquid during static sedimentation are considered. Simulation of the oily liquid preparation process was carried out in compliance with the temperature and time conditions of operation, with the use of demulsifiers, by analogy with the process of oily liquid preparation, as at the unit. The results of the simulation showed that at the dosage of the demulsifiers used at the unit, even with an increase in the dosage and an increase in the settling time to 5 days, the oil-water emulsion did not collapse at 60 0C. Further studies were carried out by testing eight brands of demulsifiers at different dosages and elevated temperatures. Based on the results of the research and the conclusions made, a scheme for the preparation of oil-containing liquid at static sludge with the existing set of equipment at the unit is proposed.Further studies were carried out to increase the depth and sedimentation rate of the persistent oil-water emulsion.

Synthesis and Kinetics of CO2-Responsive Gemini Surfactants.

Surfactants are hailed as "industrial monosodium glutamate", and are widely used as emulsifiers, demulsifiers, water treatment agents, etc., in the petroleum industry. However, due to the unidirectivity of conventional surfactants, the difficulty in demulsifying petroleum emulsions generated after emulsification with such surfactants increases sharply. Therefore, it is of great significance and application value to design and develop a novel switchable surfactant for oil exploitation. In this study, a CO2-switchable Gemini surfactant of N,N'-dimethyl-N,N'-didodecyl butylene diamine (DMDBA) was synthesized from 1, 4-dibromobutane, dodecylamine, formic acid, and formaldehyde. Then, the synthesized surfactant was structurally characterized by infrared (IR) spectroscopy, hydrogen nuclear magnetic resonance (1H NMR) spectroscopy, and electrospray ionization mass spectrometry (ESI-MS); the changes in conductivity and Zeta potential of DMDBA before and after CO2/N2 injection were also studied. The results show that DMDBA had a good CO2 response and cycle reversibility. The critical micelle concentration (CMC) of cationic surfactant obtained from DMDBA by injecting CO2 was 1.45 × 10-4 mol/L, the surface tension at CMC was 33.4 mN·m-1, and the contact angle with paraffin was less than 90°, indicating that it had a good surface activity and wettability. In addition, the kinetic law of the process of producing surfactant by injecting CO2 was studied, and it was found that the process was a second-order reaction. The influence of temperature and gas velocity on the reaction dynamics was explored. The calculated values from the equation were in good agreement with the measured values, with a correlation coefficient greater than 0.9950. The activation energy measured during the formation of surfactant was Ea = 91.16 kJ/mol.

Influence of incubation temperature on embryonic Days 4–7 on gene expression, M. pectoralis and M. gastrocnemius microstructure, and tibia characteristics in Ross 308 Broilers

ABSTRACT The incubation temperature can influence chicken bone and muscle development, and breast and leg muscles may respond differently to changes therein. Ross 308 broiler eggs were incubated at 36.5°C, 37.5°C (control), 38.5°C and 39.0°C on embryonic days 4–7. M. pectoralis and M. gastrocnemius were sampled at hatching and 5 weeks post-hatching, and differences in gene expression, microstructure and energy metabolism were examined. Tibia strength was tested, and gait scoring was performed. Broiler performance was similar at slaughter age, but initial growth was slowed by the 36.5°C treatment. The 38.5°C treatment reduced the M. gastrocnemius weight and shifted the M. pectoralis/M. gastrocnemius ratio. All treatments reduced M. gastrocnemius glycogen content relative to the control. The expression of single myogenesis-related genes was altered in the M. pectoralis by 36.5°C. The results indicate that the incubation temperature influences broiler muscle energy metabolism, and that the temperature of 38.5°C hampers leg muscle development.

Fiber laser-based two-wavelength sensors for detecting temperature and strain on concrete structures

In this article, we discuss the scientific research we conducted to ensure information security on concrete structures using the fiber Bragg grating method. As a result, guided by the experiences of other researchers and their results in our studies, the main hazards were identified, and the influence of temperature and deformation sensors in concrete was studied. The work determines the dependence of temperature on the optical cable and its effect on concrete deformation. It also studies the change in the internal structure of the optical fiber when exposed to concrete, and in comparison, with non-concrete optical fiber. In the experimental chapter, conducted on laboratory bench, we consider and study the signal transmission structure of an optical sensor that experiences deformation upon impact with concrete and such fibers. Graphic data was obtained using the OptiSystem program. During the process of determining the optical power of the sensors, we discovered that the higher the vibration during signal transmission, the higher the power of the optical data acquisition system unit. The results presented in this paper show the promise of fiber optics in other environments, as well as new discoveries in the construction industry and the successful use of electrical laser sensors to maintain temperature and stress in a variety of concrete structures, including cooling towers in nuclear and thermal power plants.

The influence of temperature and genomic variation on intracranial EEG measures in people with epilepsy.

Heatwaves have serious impacts on human health and constitute a key health concern from anthropogenic climate change. People have different individual tolerance for heatwaves or unaccustomed temperatures. Those with epilepsy may be particularly affected by temperature as the electroclinical hallmarks of brain excitability in epilepsy (inter-ictal epileptiform discharges and seizures) are influenced by a range of physiological and non-physiological conditions. Heatwaves are becoming more common and may affect brain excitability. Leveraging spontaneous heatwaves during periods of intracranial EEG recording in participants with epilepsy in a non-air-conditioned telemetry unit at the National Hospital for Neurology and Neurosurgery in London from May to August 2015-22, we examined the impact of heatwaves on brain excitability. In London, a heatwave is defined as three or more consecutive days with daily maximum temperatures ≥28°C. For each participant, we counted inter-ictal epileptiform discharges using four 10-min segments within, and outside of, heatwaves during periods of intracranial EEG recording. Additionally, we counted all clinical and subclinical seizures within, and outside of, heatwaves. We searched for causal rare genetic variants and calculated the epilepsy PRS. Nine participants were included in the study (six men, three women), median age 30 years (range 24-39). During heatwaves, there was a significant increase in the number of inter-ictal epileptiform discharges in three participants. Five participants had more seizures during the heatwave period, and as a group, there were significantly more seizures during the heatwaves. Genetic data, available for eight participants, showed none had known rare, genetically-determined epilepsies, whilst all had high polygenic risk scores for epilepsy. For some people with epilepsy, and not just those with known, rare, temperature-sensitive epilepsies, there is an association between heatwaves and increased brain excitability. These preliminary data require further validation and exploration, as they raise concerns about the impact of heatwaves directly on brain health.

Rapid Synthesis and Sintering of La2O2S and Its Physical, Optical, and Mechanical Properties

Rare-earth oxysulfides are a class of functional ceramic materials with excellent physico-chemical properties and rich functionality. In this study, La2O2S powders were prepared from La2S3 and La2O3 powders at 1000 °C by pressureless sintering. La2O2S compacts were synthesized from La2S3 and La2O3 powders at 800–1600 °C by spark plasma sintering. The influences of sintering temperature and time on the preparation of La2O2S were studied. XRD results indicated that La2O2S ceramics were synthesized successfully and that the lattice constants of La2O2S were close to the theoretical values. SEM showed that the microstructure of La2O2S compacts was homogeneous. The specific heat of La2O2S mainly came from lattice contribution, and its Debye temperature was 237 K. The UV–visible absorption spectra showed different absorption levels in the 240–300 nm range. Raman spectroscopy revealed distinct peaks at different temperatures, indicating changes in the covalence band. The relative density of La2O2S ceramics was 92% and lower than theoretical values. Hardness of the synthesized La2O2S was greater than that of Gd2O2S ceramics.

Rapid Detection of Ultralow H2S Concentration with on-chip Fabrication of SnO2-based Gas Sensors by Direct Electrodeposition from Non-Aqueous Solvents

Hydrogen sulfide (H2S) causes significant impacts on human health and the environment due to its highly toxic properties. Thus, the design and development of gas sensors to detect and monitor H2S (especially at extremely low concentrations) are challenging tasks for scientists. In this work, SnO2 gas sensors were successfully synthesized directly on a chip by Sn electrodeposition from ethylene glycol solutions + a post-treatment (calcination) stage (to form and stabilize SnO2). Mechanisms and kinetics of Sn electrodeposition on Pt microelectrodes were thoroughly studied using electrochemical techniques. These fabricated gas sensors exhibit a high selectivity toward H2S gas and an effective response to low-level concentrations of H2S in the range of 0.1 ppm–1 ppm at different working temperatures. The influence of electrodeposition conditions and calcination temperatures on the gas response of sensors were also examined. The results have verified that the electrodeposition method from ethylene glycol solutions is promising for the fabrication of ultrasensitive on-chip gas sensors.

Preparation and Properties of Nb5+-Doped BCZT-Based Ceramic Thick Films by Scraping Process.

A bottleneck characterized by high strain and low hysteresis has constantly existed in the design process of piezoelectric actuators. In order to solve the problem that actuator materials cannot simultaneously exhibit large strain and low hysteresis under relatively high electric fields, Nb5+-doped 0.975(Ba0.85Ca0.15)[(Zr0.1Ti0.9)0.999Nb0.001]O3-0.025(Bi0.5Na0.5)ZrO3 (BCZTNb0.001-0.025BiNZ) ceramic thick films were prepared by a film scraping process combined with a solid-state twin crystal method, and the influence of sintering temperature was studied systematically. All BCZTNb0.001-0.025BiNZ ceramic thick films sintered at different sintering temperatures have a pure perovskite structure with multiphase coexistence, dense microstructure and typical dielectric relaxation behavior. The conduction mechanism of all samples at high temperatures is dominated by oxygen vacancies confirmed by linear fitting using the Arrhenius law. As the sintering temperature elevates, the grain size increases, inducing the improvement of dielectric, ferroelectric and field-induced strain performance. The 1325 °C sintered BCZTNb0.001-0.025BiNZ ceramic thick film has the lowest hysteresis (1.34%) and relatively large unipolar strain (0.104%) at 60 kV/cm, showing relatively large strain and nearly zero strain hysteresis compared with most previously reported lead-free piezoelectric ceramics and presenting favorable application prospects in the actuator field.

Elevated temperature exacerbates pharmaceutical-induced oxidative stress in zebrafish (Danio rerio) larvae

There is growing evidence that rising global temperatures resulting from climate change may exacerbate the toxic effect of pollutants and heterotherms, including fish, in which homestatic mechanisms are directly influenced by environmental temperature will be most affected. Pharmaceuticals discharged into the environment are potentially harmful to wildlife as many of their drug targets are conserved across divergent phyla. Oxidative stress (OS) is a major mechanism by which many pharmaceutical contaminants can induce toxicity but this has received little consideration in the context of effects in wildlife. Further, these mechanisms are relatively poorly understood, particularly regarding multiple stressor interactions. We used transgenic TG(EpRE:mCherry) zebrafish, developed in our laboratory for detecting OS, as our experimental model. We show that the oxidative effects of high concentrations of pharmaceuticals from three different therapeutic classes (paracetamol, diclofenac and doxorubicin) are increased at temperatures elevated by 2–5 °C above those for zebrafish standard husbandry and relevant to their current natural environment (and predicted under the IPCC 2023 scenarios for intermediate to very high greenhouse gas emissions). These OS responses were primarily seen in the pronephros, liver, and gastrointestinal tract. The increase in OS at the increased water temperature may have resulted from the elevated temperature acting as a direct additive physiological stressor to the OS imposed by the drugs and/or via the temperature increasing the chemicals oxidative effect. For paracetamol, it appeared that the elevated responses at the higher temperature of 33 °C were in part due to an increase in uptake of the drug. Our data illustrate that risk assessments for chemicals inducing OS in fish (and likely other heterotherms) should consider the influence of temperature to ensure environmental protection in future environments.

Adhesive-capable film materials for PCM

This paper considers the possibility of joining layers of polymer composite materials (PCM) with adhesives based on chemically modified polyethylene. The adhesive strength between epoxy fiberglass and adhesives (various ethylene copolymers) was investigated. The influence of temperature and pressure on the adhesion between materials has been studied.

Employing a multi-resonance microwave sensor for in-line moisture monitoring of fluidized bed agglomeration

Amorphous substances are relatively common in food industry and their characteristics depend highly on the moisture content. Process parameters are adjusted based on online measurements to control the product quality of the agglomerates. This leads to two major challenges: precise moisture content measurements of amorphous particles at (i) different temperatures and for (ii) a wide moisture content range.In this study two workflows (inline fluidized bed and conditioned fixed bed) calibration of microwave sensors are compared and it is shown that for fluidized beds inline calibration is necessary to achieve accurate moisture measurements. The application of the novel microwave sensor MW 4200 working at resonance frequencies of 2.3 and 5.6 GHz is described. The temperature influence on the measurement is investigated with measurements of a fixed particle bed. Rapid, reliable in-process moisture control at a wide range of moisture contents and temperatures for agglomeration in fluidized beds, with a mean relative accuracy of 82 %, is achieved. This technology improves productivity and precision in industrial operations, minimizes waste and optimizes energy usage.